Reasons
He stared at the key, and found himself having a shortness of breath. All the chances he once had were now gone.
'I have to gain my honor back!'
Did he really run towards that? Did he really enter the race, HIS race for that reason? Or was he just running away like he always did? Running like the devil was chasing him, just like the coward he was.
'I'm sorry for whatever happened that made you stop believing, but It's all real!'
Oh god, he wished it wasn't real. He wished that this had never happened to him. He wish he could run away from the truth, just like he had run away from everything else. Just one simple turn. All he had to do was turn the bloody key. He was not like Kelvin. He was not like Kelvin…
'So I started pushing the button too. And we saved the world together for a while, and that was lovely. Then Kelvin died, and now here I am all alone. The end.'
There was nothing else he could do. No matter what he could never escape from the hatch. It became his life, his habit, his routine, his addiction that he never wanted. This was the only way. If it wasn't for Penelope he wouldn't have made it this far, being alone for so long…
'Because all we really need to survive is one person who truly loves us. And you have her. I will wait for you. Always. I love you.'
"I love you Penny!"
Desmond shuddered. As sweat poured off him, he spoke his last words of hope he would ever say. He ignored the intense fear in his heart, and tightened his grip on the key. He took a deep breath, and turned the key to the fail-safe.
Finally ending the place that ruined his life.
Finally ending it all…
"God bless you Pen…goodbye."
His world turned white.